An early event thought to participate in the pathogenesis of IBD is the disruption of the gastrointestinal epithelial barrier. This disruption leads to the mixing of microbial pathogens from lmen with antigen presenting cells in the lamina propria producing an inflammatory response. The resulting pro-inflammatory cytokines and chemokines recruit and activate leukocytes, regulate the integrity of the epithelial barrier and stimulate the production of chemokines from epithelial cells. Together these events lead to the inflammation of the intestines.

Figure: HT29 cells were stimulated with TNF-a for 24 hours in the presence of vehicle control and ECGC. Cell culture supernatants were assays for IP-10, IL-8, MIP-3a and PGE2. Mean values are shown. Error bars represent standard deviations.